The invention relates to a separator for separating curable material including liquid, especially residual concrete, residual mortar and the like, using a conveying screw in a trough, and particularly relates to the conveying screw and trough design.
Apparatus of the type mentioned here are employed, for example, in ready-mix concrete plants. They take up unset residues of curable material, such as concrete, mortar and the like, and subject the material to extractive washing using a liquid, so that the individual components of the washed material can be returned to the production process. For this purpose the material is introduced into the separator, where it is separated from the cement paste by use of water. Material which has been washed out, for example, sand, gravel and the like, is conveyed out of the separator by mechanical means and is temporarily stored in a material box. The water that extractively washed the material is introduced from the separator into a container, which is preferably provided with a circulation apparatus in order to prevent settling of the fines and of the cement paste. The wash water can likewise be reused to produce fresh concrete, mortar, and the like.
DE 39 28 528 C2 discloses a separator of this type comprising a cylindrical transport screw which is disposed in a receiving trough having a floor which runs parallel to the horizontal. The aggregates which have been washed out, sand and gravel, for example, are discharged from the partly liquid filled receiving trough with the aid of a bucket wheel. Those aggregates are emptied into a second conveying apparatus comprising a conveying conduit which extends transversely to the horizontal and a conveying screw which is disposed in that conduit. Disadvantages of this configuration which the high costs for the second conveying means and the large constructional area for the separator.
DE 39 06 645 C2 discloses a separator having a conveying screw which is disposed in a receiving trough. At its lower end, the screw has a cylindrical region and, following that, a conical region. The floor of the receiving trough, which is at the cylindrical region or the conveying screw, runs transversely to one horizontal. The separator has only a small water bath, whereby its capacity, and the quality of extractive washing, are low.